If you have a low sex drive, can't get off, or you have fertility issues, you're not alone. In fact, you're far from alone! About 40 to 70 percent of men experience some kind of sexual dysfunction in their lifetime, according to research from the Wake Forest Baptist Medical Center.

Problem is, when it comes to your penis, it's a sensitive subject. Men are far less inclined to go to a doctor in the first place, let alone disclose their medical problems. So, many turn to over-the-counter supplements rather than go through the perceived embarrassment of their sexual faults and receive a prescription. That's not to say supplements aren't helpful in providing optimal health (even for your Johnson); but there are so many formulations, and little regulation over standards and appropriate dosages that it can be easy to do your body a disservice.

Before you begin taking any supplement, speak with your doctor for appropriate dosage, possible side effects to medications you're currently taking, and advice on what might be best for you. 

That said, here's a guide of supplements either to be used alone or in tandem with others to treat common men's sexual health issues. These options have been backed by research and/or given a nod from Wake Forest Baptist Medical Center's 2016 review, which dissected all scientific evidence behind the effectiveness of common sex supplements' ingredients and safety. (Also check out some of the best supps for your penis.)

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1. DHEA
Best usage: Enhancing sex drive, minimizing erectile dysfunction

DHEA is a hormone produced by the adrenal glands, which your body then uses to produce sex hormones, according to research from the Wake Forest Baptist Medical Center. Daily supplements may benefit people with decreased libido, improve sexual function, and minimize erectile dysfunction in men, per the Mayo Clinic. And, while there's good scientific evidence for DHEA's ability to bolster your sex life, studies have flip-flopped in terms of consistency; more data needs to be done to suggest the full range of its benefits and side effects. 

2. Fenugreek
Best usage: Intensifying sexual arousal and orgasms, reducing recovery time

You'll find this herbal extract in about a third of the top-selling men's health supplements, per Wake Forest Baptist Medical Center. One study published in the journal Phytotherapy Research found men who took the supplement experienced an 82 percent increase in libido (more intense arousal) after six weeks. What's more, 63 percent of the men taking fenugreek enjoyed a boost in sexual performance (stronger orgasms), 67 percent said the supp enhanced their sexual recovery time, and even promoted greater muscle strength, overall energy, and well-being. No participants reported negative side effects; plus, other studies back it up.

3. Ginseng
Best usage: Bolster overall sexual health, including proper penile function, libido, performance, sperm quality

Ginseng is a super power herb that's long been touted as an aphrodisiac, treatment for erectile dysfunction, and overall sex enhancer in traditional Chinese medical practice; it's also the most common ingredient in men's sexual health supplements, according to Wake Forest Baptist Medical Center. An animal study published in British Pharmacological Society discovered ginseng has a favorable effect on libido and sexual performance, which crosses over into human models, too. Ginseng improved the sperm quality and count of healthy men, as well those with fertility issues. In another study, 45 men with moderate to severe erectile dysfunction had marked improvements with regards to performance and sexual satisfaction after supplementing three times a day with 900mg Korean red ginseng for 8 weeks. And, yet another study, published in the Journal of Urology, discovered ginseng helped men with erectile dysfunction enjoy better performance—greater rigidity, penetration, and maintenance of erections—after taking 1,000mg of Korean red ginseng three times a day for 12 weeks.

4. L-citrulline
Best usage: Combat erectile dysfunction, boost sexual satisfaction 

L-arginine may be the most common amino acid present in men's health supplements, per Wake Forest Baptist Medical Center, but it's metabolized too quickly for there to be any real benefit, according to research published in Urology. That's why L-citrulline, which your body converts to L-arginine, is a better choice. In a small study, done on men with mild erectile dysfunction, L-citrulline supps (1.5g per day for one month) amplified 50 percent of participants' erection hardness scores from 3 (mild ED) to 4 (normal erectile function). Men also reported having more sex and were very satisfied with the results. Overall, l-citrulline has been proven safe and psychologically well accepted by patients with ED, researchers say. 

5. Maca
Best usage: Stronger sex drive, sperm function

More studies are warranted, but a systematic review of research across 17 different databases found evidence for the effectiveness of maca in the improvement of sexual function. One in particular, published in Andrologia, found 40 percent of men who took maca plant supplements for three months experienced a stronger sex drive, as well as improved sperm formation and movement.

6. Yohimbine
Best usage: Minimize erectile dysfunction

If you're feeling deflated in more ways than one, Yohimbine—the bark of an evergreen tree native to Africa—can help by widening blood vessels and lowering blood pressure, increasing the health of your sexual organs, yielding firmer erections, and combating erectile dysfunction, according to a meta-analysis published in Wiley. Researchers site a variety of studies in which men were given 18mg of Yohimbine per day to treat or minimize ED; in most cases the supplement didn't cause significant non-intended side effects (though in some instances men experienced anxiety and headaches in higher doses, Wake Forest Baptist Medical Center notes). In two separate studies, 34-46 percent of men had a positive outcome.

7. Vitamin E
Best usage: Healthier sperm, fertility

For stronger swimmers, vitamin E supps can help protect and foster better-quality sperm, according to research published in the International Journal of General Medicine. Nearly 700 infertile men took 200 μg (micrograms) with 400 IU (units) of vitamin E every day for at least 100 days. Over 50 percent of the men had improvements in sperm motility and form, and roughly 11 percent of men were able to get their partner pregnant. 

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